Powered trimaran with retractable pontoons



March 19, 1968 c. E. STACEY 3,37

POWERED TRIMARAN WITH RETRACTABLE PONTOONS Filed May 4, 1966 5 Sheets-Sheet 1 23 5 68 l r I INVENTOR. CECIL EDWARD STACEY E ia- March 19, 1968 c. E. STACEY 3,373,715

POWERED TRIMARAN WITH RETRACTABLE PONTOONS Filed May 4, 1966 5 sheets-Sheet 2 /V VE NT 0R. 05cm EDWARD STACEY March 19, 1968 c. E. STACEY POWERED TRIMARAN WITH RETRACTABLE PONTOONS 3 Sheets-Sheet 5 Filed May 4, 1966 INVE/VTOR. CEC/L EDWARD STAGE) United States Patent 3,373,715 POWERED TRIMARAN WITH RETRACTABLE PONTOONS Cecil Edward Stacey, Grand Rapids, Mich. (9554 IVIyers Lake Road, Rockford, Mich. 49341) Filed May 4, 1966, Ser. No. 547,482 3 Claims. Cl. 115-70) ABSTRACT OF THE DISELOSURE A boat having oppositely disposed hull extensions which are moved outwardly to increase the stability of the boat.

This invention relates to the construction of boats, if the term boat is used in its broadest sense. More accurately, the invention provides a device that can be compared to a self-powered aquaplane. The driver-passenger rides on its rather than in it, and the preferred form of the invention utilizes a hull form and center of gravity position that results in static instability when the device is in condition for running at high speed. The directional controllability of the device makes it possible for the operator to maintain his balance as long as the speed continues. The planing characteristics of the boat will also substantially increase the stability over that corresponding to static buoyancy. If the operator cuts off the power, however, the resulting loss of speed will cause the boat to exhibit a very precarious (and possibly even negative) stability in the absence of forward speed. Prior to losing this control and stability, the operator can actuate a mechanism which extends pontoons on the opposite sides of the device, which produces asufiicient increase in static stability tokeep the boat upright.

With the pontoons retracted to the running position, it is preferable that the outside surfaces of the pontoons be more or less continuous with the central hull surfaces to produce efiicient hull lines at high speed. The device has been developed primarily for use with a small outboard motor; and unless the user is extremely confident of his ability to operate the device, a bathing suit is the recommended operators uniform. The element of skill necessary to handle the device without capsizing it injects an exciting sporting element at a relatively low cost. The small size and weight permit the use of relatively small motors, and produce a speed commonly associated with much more expensive boats.

The several features of the invention will be analyzed in detail through a discussion of the particular embodiments illustrated in the accompanying drawings. In the drawings:

FIGURE 1 is a perspective view of a complete boat embodying the preferred form of the invention.

FIGURE 2 is a plan view, partially in section, showing the actuating mechanism for moving the pontoons.

FIGURE 3 is a side elevation of the boat shown in FIGURE 1.

FIGURE 4 is a front elevation of the boat shown in FIGURE 1.

FIGURE 5 is a rear elevation of the boat shown in FIGURE 1.

FIGURE 6 shows a perspective view of the primary frame elements used to position the components of the retracting mechanism.

FIGURE 7 is a schematic plan view showing the retracted condition of the pontoons.

FIGURE 8 is a schematic view showing the extended position of the pontoons.

FIGURE 9 is a schematic view of a modified from of the invention.

The boat illustrated in the drawings includes the central hull 20 with a narrowed aft portion 21 producing offate sets occupied by the pontoons 22 and 23 in the running condition of the boat. An outboard motor is normally attached to the stern bracket 24, and the operator sits somewhat precariously on the seat 25. A fixed column 26 supports the shaft assembly 27 which traverses the central hull 20, and is attached to the front rudder 28. If desired, the shaft assembly 27 may include a coupling so that the column 26 may be detached, together with the handle bar 29, as a sub-assembly.

With the boat in the condition shown in FIGURES 1 through 5 and 8, it is capable of running at high speeds with a fairly respectable degree of planing stability. This stability is supplemented by the directional control provided by the steering arrangement, which makes the operator able to control the balance of the device in some what the same manner as one would a bicycle. The hull form in cross section (which appears best in FIGURES 4 and 5) is such that the moment forward speed is lost, the relatively high position of the center of gravity resulting from the operators position (and the position of the motor) will produce a condition similar to a person standing up in a canoe. The slightest move will result in capsizing the boat, and it is easily possible to produce inherent instability such that keeping the boat upright with zero forward speed becomes a genuine balancing feat.

If the operator desires to halt his forward motion, he will normally operate the lever 30, which controls a mechanism that positions the pontoons 22 and 23 laterally. These pontoons are connected to the central hull 20 by the links 31-32 and 33-34. The pins 35-36 and 3 73 8 are respectively secured to the pontoons 22 and 23, and the opposite ends of the links are connected to the pins 39-40 and 41-42 respectively mounted on the frame elements 43 and 44. Preferably, these same frame elements are provided with the extensions 45 and 46 which serve as supports for the seat 25". The flanges 47 and 48 may be bolted to the central aft portion 21. The vertical flanges 49 and 50 support the motor bracket panel 24 at the proper position. The central area between the frame elements 43 and 44 can also be used for the equipment associated with the operation of the motor. Because of the presence of the forward rudder 28, it is preferable to incorporate the double skeg arrangement which appears best in FIGURES 4 and 5. The skegs 51 and 52 are preferably merely a pair of bent aluminum plates, with the upper portion secured to the sides of the portion 21 of the central hull, with the portions below the bend line extending below the hull outline.

When it becomes desirable to increase the stability of the device in roll, the actuation of the handle 30 operates the linkage shown in FIGURE 2. The handle 30 is rotatably mounted on the shaft 53, which is equipped with the radius arms 54 and 55. The push rods 56 and 57 are connected to the bar 58 extending between the outer extremities of the arms 54 and 55, and the opposite ends of these push rods are connected to the bell cranks 59 and 60 pivotally mounted on the central beam 61 extending across between the frame elements 43 and 44. Motion of the bell cranks is communicated to the links 32 and 34 by the intermediate links 59a and 60a. To avoid an undesirable dead center position of the links 31-34 (and a corresponding indeterminate pontoon position), the auxiliary links 62 and 63 are connected at pivot points on the links 31-34 which are angularly displaced by a constant amount (about the axes of the pins 39-42) from the positions of the pins 3538. In the schematic views shown in FIGURES 7 and 8, an outboard motor is generally indicated at 64, and this motor may be any one of the currently available standard outboard motors of intermediate size. Five or ten horsepower in a boat of this type will produce some rather surprising speeds.

The construction of the central hull 20 and the pontoons 22 and 23 may be of a hollow shell-type commonly associated with boat construction, and may utilize either plywood or conventional planking arrangements. Alternatively, the central hull 2t} and the pontoons may be molded of a foamed plastic material. The technique for molding objects in this condition is well known. In either type of construction, it is preferable that the line of junction (indicated at 68 in FIGURE 1) between the pontoons and the central hull be inclined forwardly and upwardly to minimize the tendency to produce a spray of water at high speed. The total floatation of the device should certainly be designed with respect to the particular motor for which it is intended. It is also desirable that the steering handle 29 be provided with conventional throttle controls and a switch governing the ignition of the motor, with the switch arranged so that any relaxing of the grip of the operator will immediately shut off the engine. An engine can be severely damaged by taking solid water in at the intake, which is likely to be the result in the event that the device capsizes with the motor running.

The particular linkage for moving the pontoons laterally can be selected according to convenience. The movement from a retracted position to a stabilizing position can result from hinging the pontoons 65 to the top of the central hull 66 at 67 on front-rear axes as shown in FIG- URE 9 with the resulting retracted position being above the hinge connection (and possibly swung over on top of the hull). A control rod 68 can be used to position the pontoons.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appended claims. In these claims, it is my intent to claim the entire invention disclosed herein, except as I am limited by the prior art.

I claim:

1. A boat, comprising:

a central hull having recesses in the opposite sides thereof; and pontoons secured to opposite sides of said central hull, respectively, for lateral movement with respect thereto between an extended position spaced from said hull and a retracted position adjacent said hull, said pontoons occupying said recesses in said retracted position to form a continuation of the exposed surfaces of said hull, said pontoons each being connected to said hull by spaced parallel links, said links being interconnected by auxiliary link means, and positioned by intermediate link means connected to one of said parallel links and to a crank means mounted on said hull, said crank means being operatively connected to a manually-controlled actuating mechanism.

2. A boat as defined in claim 1, wherein said pontoon forms an uninterrupted continuation of a part of the bottom and side surfaces of said boat, when in said retracted position.

3. A boat as defined in claim 1, wherein said central hull has seat means and motor-receiving means, and said boat is formed in cross-section to be unstable in roll with said pontoon in retracted position, and stable in roll with said pontoon in extended position.

References Cited UNITED STATES PATENTS 2,678,018 5/1954 Crisp 1l4l23 3,150,632 9/1964 Evans 1l570 3,276,413 10/1966 Dolph et a1. 114-123 3,294,055 12/ 1966 McGuire 1l5--70 MILTON BUCHLER, Primary Examiner.

T. M. BLIX, Assistant Examiner. 

